- The Crusades
- The French-speaking world in the central Middle Ages, especially in relation to the Mediterranean
- Social and geographical mobility
My research focuses on social and geographical mobility during the central Middle Ages – and, in particular, during the epoch of the Crusades. My publications include John of Brienne: King of Jerusalem, Latin Emperor of Constantinople, c.1175-1237 (Cambridge: Cambridge University Press, 2013); The Briennes: the Rise and Fall of a Champenois Dynasty in the Age of the Crusades, c.950-1356 (Cambridge: Cambridge University Press, 2018); and a co-edited volume, The Fifth Crusade in Context: the Crusading Movement in the Early Thirteenth Century (Abingdon: Routledge, 2017).